Zwilling/Henckel's has several sub-brands. Those you bought are sold under the "J.A. Henckel's International" brand, which was created specifically for the "value" knife segment (meaning, inexpensive). Henckel's has for quite a while sold knives made outside of Germany. Usually in Spain and China, and some products just listed as made in Asia, which is a pretty big place.
Per their web site (
http://www.zwillingonline.com/jhein1.html)
The J.A. HENCKELS INTERNATIONAL brand was established in 1895 as a separate value brand of ZWILLING J.A. HENCKELS. J.A. HENCKELS INTERNATIONAL produces knives for the value conscious customer who wants a quality product for their everyday needs at the best price.
The bold italics is mine, and are the code words in advertising copy meaning "this is the cheap stuff that we sell at Wal-Mart."
The specific product line you mentioned, the Silvercap, is described thus on their web page (
http://www.zwillingonline.com/j-a-henckels-international-silvercap.html):
J.A. Henckels International Silvercap
• Micro serrated blade , never needs to be sharpened.
• Molded ergonomic black handle
• Endcap features lasered Henckels International Logo
• Dishwasher safe
• Made in China
When you see "dishwasher safe" and "never needs to be sharpened" it's not a top quality kitchen knife.
If you look at their main US web site,
https://www.zwilling.com/us/en/categories/cutlery.html, you will not see any of the "value brand" knives listed, just their made-in-Germany products (with a few exceptions in the accessory or specialty products line).
The lowest cost Zwilling-Henckel's line that is made in Germany is their Twin Signature line. They
don't* apparently do get the same "Friodur" ice-hardening process that the other Zwilling knives get, and are believed to be the same X50CrMoV15 used in most of their German-made knives.
We have a Henckels International 6" chefs knife that my wife bought a few years ago, which is very similar in design to the current Twin Signature, but was made in China. It is not a bad knife, and has a regular edge that can be sharpened easily enough. I am guessing the hardness is about 55 HRC, which same as the current Twin Signature.
I also have one of their mid-tier "Zwilling J.A. Henckels Pro" line, the 5 1/4" Prep Knife, which is a convenient size with a good profile. It's a decent knife that seems well made. 58 HRC hardness on that one, according to reputable sources.
*Edited to correct an error in my understanding.